Remote controlling apparatus



June 29, 1937. A B WLLER 2,085,438

REMOTE CONTROLLING APPARATUS Original Filed Oct. 9, 1929 2 Sheets-Sheet 1 45 V 64118 A 57 C June 29, 1937. v 2,085,438

REMOTE CONTROLLING APPARATUS Original Filed Oct. 9, 1929 2 Sheets-Sheet 2 Siafiolz B Despazcizens Office INVENTOR:

Patented June 29, 1937 UNE'E'ED dTATsES PATENT @FFICE REMOTE CONTROLLENG APPARATUS Application October 9, 1929, Serial No. 398,343 Renewed November 2, 1935 55 Claims.

My invention relates to remote controlling apparatus, and particularly to apparatus of the type comprising a plurality of communication channels extending between two spaced points,

together with means for selectively controlling such channels individually or in combination to produce distinctive code elements for transmitting signals from one point to another. Apparatus embodying my invention is suitable for,

though in no way limited to, use in a centralized trafiic controlling system for railroads adapted for controlling a plurality of train governing devices, such as railway switches, or signals, or both, from a remote point such, for example, as

a train dispatchers office; and for also communicating to said office the condition of such devices and other information, such as the presence of trains adjacent such devices.

The apparatus of my invention is an improvement upon that disclosed in the several applications herein referred to, and also upon that disclosed in the following pending applications for Railway traflic controlling apparatus: H. A. Wallace, Serial NO. 125,659, filed July 29, 1926; L. V. Lewis, Serial No. 254,690, filed February 16, 1928; and G. W. Baughman, Serial No. 255,375, filed February 18, 1928. It is also an improvement upon that disclosed in the pending Lewis application, Serial No. 291,465, filed July 9, 1928, for Remote controlling apparatus.

In systems of the type described, it is customary to supply control codes to a line circuit or line circuits extending betwen the dispatchers office and the remote point at which the governing devices are located for effecting the control of these devices, and to deliver indication codes to this line circuit or to these line circuits from the remote point for informing the dispatcher concerning the condition of the devices. In at least one system which has been previously suggested, the codes employed for these purposes are made up of code elements having different characters which separately actuate individual receiving devices, and apparatus is also provided which is selectively responsive to the sequence of operation of these receiving devices. In my present invention I utilize apparatus which is responsive to the sequence in which code elements of different characters are received, but I prefer to employ receiving devices which are controlled directly .from the point at which the control code or indication code originates. In a. preferred embodiment of my invention I provide a, plurality of line circuit or indication channels extending from the dispatchers office to each of the remote points at which it is desired to operate governing devices, certain of which circuits or channels may have a common return wire. With this arrangement it will be apparent that I can produce code elements of difierent 5 characters by supplying impulses to different line circuits, and that I can produce code elements having still other characters by supplying impulses simultaneously to combinations of these line circuits. 10

I will describe one form of remote controlling apparatus embodying my invention, and will then pointout the novel features thereof in claims.

In the accompanying drawings, Figs. 1 and 2 when placed end to end with Fig. 1 on the left 15 form a diagrammatic view showing one form of remote controlling apparatus embodying my invention. Fig. 1 ilustrates the apparatus located at the dispatchers ofiice, and Fig. 2 illustrates the apparatus located at a remote point.

Similar reference characters refer to similar parts in both views.

Referring now to the drawings, it will be seen that three line wires, designated by the reference characters I, 2 and 3 extend from the dis patchers ofiice to each of the remote stations controlled from this oflice. Line wire 3 serves as a common return for two line circuits, one including line wire 1 and the other including line wire 2. Two line relays are located at the dispatchers office and two similar line relays are located at each remote station, each designated by the reference character R with a prefix corresponding to the location and a suitable distinguishing suflix. Each line relay is included in series in one of the line circuits made up of the common wire 3 and one of the line wires I or 2. For example, at the dispatchers ofiice, line relay ARI is included in series with line wire l. Current is normally supplied to 0 both line circuits from batteries each designated by the reference character 4 with a suitable distinguishing exponent and one located at the dispatchers office and at each remote station. Since both line circuits are normally closed, it 5 follows that all line relays R are normally energized.

For the purpose of delivering control codes to the line circuits, the dispatchers office is provided with a plurality of panels, one for each remote station which is to be controlled from the dispatchers ofiice, and each panel is provided with manually controlled switching devices for separately controlling governing devices at the associated station. Referring particularly to panel B on Fig. 1, this panel is provided with two stitching devices BE! and BE2 each comprising a lever i2, which as here shown is in the form of a cam which operates a cam follower E3. The lever l2 also controls a movable contact M which may be moved into engagement with a selected one of a plurality of fixed contacts. The switching devices BE! and BE2 jointly control a movable member 88 which is pivoted at point w and which is arranged to swing in a clockwise direction about point i 8 when either switching device is operated. When the member It is operated, contact arm 25 is moved out of engagement with contact 22 which it normally engages, and is swung into engagement with contact if. This movement of arm permits a latch 23 to drop under the influence of gravity to a position in which the return of arm 29 is prevented.

Each panel is also provided with a code setting 20 relay, designated by the reference character W with a prefix corresponding to the panel, and having a winding which controls a finger 24 and a plurality of contacts. When winding 25 of relay BW is energized, the finger 2a is swung to the 25 left and the tip of this finger then engages the arm 20 and at the same time lifts the latch 23. Under these conditions therefore the arm 2c is unlatched, but is held in its left-hand position, so that contact 2l!2i is closed, until winding 25 is de-energized.

The switching device BE! may be employed as a switch lever to operate a railway switch at one of the remote stations, and when the lever E2 of switching device BEi occupies the normal position shown in the drawings, contact l4l6 is closed. If the lever is operated to its reverse position, however, contact Ml5 becomes closed. The switching device BEE may be utilized as a signal lever togovern railway signals at the same station and when lever 52 of switching device BEZ occupies the normal position illustrated in the drawings, contact M l 5 is closed. If lever i2 is swung to the left, contact l4i 5 is closed, and if lever 12 is swung to the right, contact M-ll is closed.

For the purpose of delivering code elements to the line circuits I have provided transmitting relays at the dispatchers office and at each remote station. Referring for example to Fig. 1, I have shown three transmitting relays ATl, ATE and AT3. Relay ATI has a back contact 38 normally included in the line circuit including line wires I and 3 so that when this relay is energized, relay AR! is de-energized and line I is opened. In similar manner the opening of back contact 39 of relay ATZ de-energizes relay ARZ and opens line wire 2. When relay AT3 is energized, the opening of back contacts 4!] and M de-energizes both line relays ARI and ARE and opens both line wires l and 2.

The transmitting relays ATl, ATZ and AT3 and the corresponding relays at each station are operated in different sequences to produce different control codes, each made up of a plurality of code elements during which one or more of the line circuits is open. The transmitting relays at the dispatchers ofiice are controlled in part by the switching devices E on the control panels at the dispatchers office and also by a group of relays, one function of which is to prevent interference between codes originating at different stations. The transmitting relays at each location are also controlled by a stepping contactor similar in all respects to the stepping contactor which is described and claimed in an application for Letters Patent, Serial No. 362,948, filed by Clarence S. Snavely on May 14, 1929, for Remote controlling apparatus. Referring particularly to the apparatus at the dispatchers office, stepping contactor P comprises a spider 26 operated by a pawl 65 driven by a magnet F This spider co-operates with a plurality of fixed contact segments designated by the reference characters 21 to 34 and arranged in such manner that an arm of the spider engages one of these segments at all times. As shown in the drawings, the spider engages segment 27!. If, now, the magnet F is energized, pawl 65 is moved along one tooth on the spider 26 and when the magnet F is next de energized, the spider 26 is advanced one step so that an arm of the spider then engages contact 28. In similar manner successive energizations and de-energizations of the stepping magnet F advance the spider 26 from each segmenting of the stepping contactor to the next segment in order.

The apparatus herein shown and described may be utilized for controlling governing devices of any suitable type, but for purpose of explanation, I have illustrated at station B a section of railway track 56 provided with a switch I leading into a siding 8. The section 5-6 is provided with a track circuit including a battery 9 connected across the rails adjacent one end of the section and a track relay 1; connected across the rails adjacent the other end of the section. The switch I is controlled by a motor g comprising an armature Ill and a field l I, which motor is controlled in part by two switch relays p and p Switch 1 in turn controls a pole-changer 35 which governs the polarity of current supplied from terminals B and C of a suitable source of energy to an indication relay k as will be apparent from the drawings. Relay is is energized in the normal direction, so that its polar contacts are swung to the left, when switch I occupies its normal position. When the switch 7 occupies its reverse position, however, relay is is energized in the reverse direction so that its polar contacts are swung to the right. When switch I occupies an intermediate position, indication relay is is deenergized so that its front contacts are open. Switch 1 also controls two contacts 36 and 31. Contact 36 is closed at all times except when the switch occupies its normal position and contact 3? is closed at all times except when the switch occupies its reverse position. Furthermore, contact 9494* is closed only when the switch occupies its normal position and contact E i-95 is closed only when the switch occupies its reverse position.

Eastbound traific through the section 5-6 is controlled by two signals w and to which, as here shown, are mounted on the same mast. In similar manner westbound traific is controlled by two signals we and w*. The signals w and 20 10 and 10 are controlled in part by two signal relays q and q The switching relays p and p and the signal relays q and q at station B are controlled by receiving apparatus which will be described in detail hereinafter.

As shown in the drawings, the switching devices BEE and BE2 on panel B at the dispatchers ofiice occupy their normal positions and switch I at station B occupies its normal position. Switch relays p and p are both de-energized and the signal relays q and are also de-energized so that all signals at station B occupy their stop positions.

In explaining the operation of the apparatus as a whole, I will first assume that the dispatcher wishes to reverse switch 'I at station B. In order to accomplish this result, he moves the switch lever I2 of switching device BEI to the reverse position. As a result the corresponding cam follower I3 is moved to the left, thereby swinging member E8 to the left and closing contact 282I At the same time contact I9 is opened. Latch 23 now engages the arm 29 and holds this arm in engagement with contact 2!. When the lever I2 has reached its full reverse position, member It returns to the position in which it is shown in the drawings, thereby closing contact I9, but contact 2ll--2I remains closed because of latch 23.

Under normal conditions a starting relay L is energized, current flowing to this relay from terminal B of a suitable source of energy over back contact 42 of relay AS, back contact 43 of relay V contact 4444 of master relay J resistor 45, contact 2ll22 of panel B, and thence through corresponding contacts on each of the remaining panels, and winding of relay L back to terminal C of the same source. The operation of the switching device BEl, just described, interrupts the normal circuit for relay L so that this relay becomes de-energized. The closing of back contact 48 of relay L completes a pick-up circuit for relay AS which may be traced from terminal B over front contact 46 of relay Q winding of relay AS, back contact 41 of relay K and back contact 48 of relay L to terminal C. Relay Q is controlled by line relays ARI and ARZ so that relay Q is energized when both line relays are closed which is, of course, the normal condition of the apparatus when no codes are being sent. The circuit for relay Q includes front contacts 58 and 59 of relay ARI and front contact 60 of relay ARZ. Relay AS therefore becomes energized over the circuit just traced, and when the front contacts of this relay become closed a branch is completed around front contact 46 of relay Q from terminal B over front contact 5| of relay AS to the right-hand terminal of relay AS. This branch comprises a stick circuit for relay AS which holds the relay in its energized condition after relay Q opens as will be described below.

When relay AS becomes energized, the opening of back contact 49 opens line wire I and the opening of back contact 50 opens line wire 2; it follows therefore that both line relays at each of the remote stations are de-energized. At the dispatchers ofli'ce, however, the energization of relay AS completes branch circuits for the line relays ARI and ARZ over which these relays are supplied with energy from battery 4 and the latter relays remain closed. A circuit is now completed, however, for relay M from terminal B over front contact 42 of relay AS, winding of relay M and back contact 52 of relay L to terminal C. Relay M therefore becomes energized, whereupon a stick circuit is completed for this relay including its own front contact 53 and back contact 52 of relay L as will be obvious from the drawings. The energization of relay M also completes a circuit for transmitting relay ATS which circuit may be traced from terminal B over front contact 53 of relay M back contact 54 of stepping magnet F contact 262'I of stepping contactor P and winding of relay AT3 to terminal C. When relay AT3 becomes energized,

the local circuits for both relays ARI and ARZ are interrupted at back contacts of relays ATS so that both line relays become de-energized and de-energize relay Q When relay Q becomes de-energized, current is supplied over back contact 46 of this relay to relays H and K in parallel so that these relays both become energized. The operation of relay H is of no particular significance at this point in the sequence of operation, but relay K opens the stick circuit for relay AS and completes a snubbing circuit for this relay which may be traced from terminal B over front contact 5i of relay AS, winding of relay AS, front contact 4? of relay K and resistor 55 to terminal B. When the snubbing circuit is closed, it will be seen that both terminals of relay AS are connected with the same terminal of the source and at the expiration of an interval of time, relay AS opens its front contacts. The releasing of relay AS restores the normal line circuits over back contacts 49 and 55), but relay AT3 is nowenergized so that the line circuits are held open.

Furthermore, the releasing of the relay AS completes a pick-up circuit for code-setting relay BW of panel B, current flowing from terminal B, over back contact 42 of relay AS, back contact 43 of relay V contact 4444 of relay J resistor 45, contact 20-2I of switching device BEE, contact i9, winding 25 of code-setting relay BW, winding of reset relay a, and front contact 55 of relay M to terminal C. The reset relay a therefore becomes energized and the code setting relay BW is also energized to draw finger 24 into engagement with arm 20. The finger 24 releases latch 23, but contact 2I]2I is now held closed by the finger 24. With finger 24 of code-setting relay BW in this position, however, contact 2D24 is closed and a circuit is completed for the righthand winding of master relay J by means of which this winding is connected across resistor 45. This circuit may be traced from one terminal of resistor 45, through contact 4444 of master relay J right-hand winding of relay J finger 24 of code-setting relay BW, contact arm 2t, and thence to the other terminal of resistor 45. The potential drop across the resistor 45 is sufficient to operate the master relay J and contact id-44 of this relay now opens and contact I 44-44 closes.

One result of this operation of master relay J is that the opening of contact 4444 opens all circuits for the remaining code-setting relays CW, etc., and prevents the operation of any additional code-setting relay until the relay BW has become de-energized and the apparatus restored to its normal condition.

Another result of the operation of master relay J is that relay 2) now becomes energized. The circuit for relay b passes from terminal B over back contact 42 of relay AS, back contact 43 of relay V contact 4444 of relay J and winding of relay 1) to terminal C. When relay b becomes energized, current flows from terminal B over front contact 56 of relay 1), back contact 5? of relay D and winding of stepping magnet F to terminal C. The stepping magnet F therefore becomes energized, advancing the pawl one tooth, and disconnecting the spider 26 from terminal B at back contact 54 of magnet F It will be remembered that the transmitting relay ATS was energized over contact 26-2'I of the stepping contactor P so that relay AT3 now becomes de-energized, thereby restoring the line circuits and allowing relays ARi and AR? to become energized provided the associated line circuits are closed at all other stations. This, of course, energizes relay Q and opens the circuits for relays H and K The two latter relays, however, have slow-acting characteristics, so that these relays bridge the brief intervals of time during which relay Q is deenergized during the transmission of codes and relays H and K remain picked up until the completion of the code.

The equipment at the dispatchers office is now in condition for the transmission of a control code, and this takes place as follows:

When the stepping magnet F became energized, a circuit was completed for relay D over front contact 53 of relay M and front contact 5 of magnet F Relay D therefore becomes energized and opens, at back contact 5? thereon, the circuit previously described for magnet F As a result, magnet F becomes de-energized, and when this happens, the pawl 65 advances the spider 26 one step into a position in which contact 2-2S is closed. Each time spider 26 engages one of the segments 28 to 33, one of the transmitting relay ATl, AT2 or ATS is energized, the particular one of these relays which is picked up depending upon the code which it is desired to transmit and which is determined by the contacts of the code-setting relay which is energized and the position of the switching devices associated therewith. For convenience in connecting the various parts, the segments of the stepping contactor are brought out to bus bars, and the terminals of the transmitting relays are also rought out to bus bars, cross connections being provided between these two sets of bus bars to produce any desired code arrangement as shown in the drawings.

Relay AT2 becomes energized when contact 26-28 of stepping contactor P is closed, the circuit for this relay passing from terminal B over front contact 53 of relay M back contact 54 of magnet F contact 2$-23 of stepping contactor P contact 66 of code setting relay BW, and winding of relay ATZ to terminal C. When relay AT? picks up, line wire '2 is interrupted to produce the first element of a control code. When magnet F became de-energized to complete the circuit just traced, relay D became de-energized, and when relay D releases, the circuit for magnet F again becomes closed, energizing the magnet and advancing the pawl 35 another step, thereby interrupting the circuit through contact 25 28 of contactor P Relay ATE therefore becomes de-energized and closes the line circuit to terminate the first code element.

When relay F becomes energized, it completes the circuit for relay D which then interrupts at back contact 5%, the circuit for magnet F and magnet F again becomes de-energized to close its back contact 55. When this happens, terminal B is again connected with spider 25 which has been moved into engagement with segment 2i? and one of the transmitting relays is now energized to deliver the second element of the code. In the particular example here illustrated, the second element of the code is produced by energizing relay ATE to open both line wires 1 and 2. The operation just described is repeated, and the stepping contactor P closes its contacts in order, so that selected code elements are delivered in a predetermined sequence in accordance with the particular code-setting relay which is energized, and the position of the associated levers l2, as Will be readily understood Without further explanation.

As will be described more in detail hereinafter, the first elements of each control code are utilized to select a particular remote station, and the number of elements required for this purpose depends, of course, upon the number of remote stations which are to be controlled. In the present example, I have provided four elements in each code for the purpose of selecting a station and it will be apparent that with this arrangement, since there are three characters of code elements, 81 stations may be controlled from the dispatchers office. The code elements following these four station selecting elements are produced by operation of selected ones or" the transmitting relays, in accordance with the function which is to be performed at the station. Thus, since contact Hil5 of switching device BEl is closed, the fifth or switch controlling element of the control code now being delivered to the line circuit and produced while contact 2 5-432 of stepping contactor is closed, results from the energization of relay AT2. In similar manner, since contact 56-46 of switching device BE2 is closed, the final or signal controlling element of the code is produced by energizing relay AT3.

After the final impulse of the control code, the next operation of the stepping contactor P brings spider 26 into engagement with segment 3%. lit hen this happens, a circuit is completed for relay V which may be traced from terminal B over front contact 53 of relay M back contact 54 of relay F contact 263d of stepping coning of front contact d3 of relay V completes a circuit for the left-hand winding of the master relay from terminal B over back contact 42 of relay AS, front contact 33 of relay V and lefthand winding of master relay J to terminal C. Relay J thereupon opens contact idim and closes contact d n-M This operation of the master relay de-energizes relay BW, relay 1) and relay a. When relay BW releases, the finger it returns to its right-hand position, thereby allowing contact 22-2ii to close. The releasing of relay b interrupts the circuit for magnet F so that when relay ID next becomes tie-energized, magnet F will remain de-energized for a brief interval of time during which the spider 26 will pause in contact with segment 34.

It will be remembered that while a control code is being transmitted, relays H and K are energized during the periods of open circuit of one or more of the line wires when either or both of relays ARi' or AR? are open, and are deenergized when both line circuits are closed, but due to their slow-release characteristics these relays remain picked up until the completion of the code.

When the spider 26 pauses on segment 55, as explained above, the line circuits both remain closed, relays K and H are deenergized and relay H releases at the end of its time interval. Relay K has a somewhat longer holding time than relay H and does not release until the expiration of a further time interval. When relay H releases, a circuit is closed for magnet F from terminal B over back contact 32 of relay AS, front contact 62 of relay M front contact 83 of relay V back contact 64 of relay H back contact 57 of relay D and winding of relay F to terminal C. Magnet F therefore becomes energized, and opens the circuit previously traced for relay V Furthermore, relay D now becomes energized, thereby again de-energizing magnet F and causing the spider 26 to be advanced into engagement with segment 21 thus returning the stepping contactor to its starting position.

The closing of back contact 43 of relay V completes the normal circuit previously traced for relay L and relay L picks up, thereby deenergizing relay M at back contact 52 of relay L In the meantime relay K has released and since magnet F and relays D H V and M are de-energized, the apparatus is now restored to its normal condition. It should be pointed out that if a switching device has been operated during the delivery of the control code, the deenergizing of relay V at the conclusion of this code will not pick up relay L but the codesetting relay for such operated switching device will then become energized and the apparatus at the dispatchers oiiice will operate to transmit the control code corresponding to the switching device which has been operated, in the same manner as just described in connection with the o eration of switching device BEI.

For example, I will assume that the switching device BE! has been operated, and that the corresponding code is being supplied to the line wires as explained above. I will also assume that during the delivery of this code, the switching device CE! is operated. The contact arm controlled by device CE! and corresponding to arm 26 operated by device BE! therefore becomes latched, but the apparatus is otherwise unaffected. At the conclusion of the code initiated by movement of device BE], relay V becomes deenergized as explained above, but since device CE! has been operated, relay L does not pick up. Instead, the circuit for code setting relay CW is closed, and the apparatus proceeds to operate the stepping contactor P and deliver the code corresponding to the setting determined by the relay CW. When the last code which has been stored in this manner has been delivered, relay L picks up and restores the apparatus to its normal condition as explained hereinbefore.

The purpose of the reset relay a is to permit the dispatcher to change a control code after the code transmission has been started, without requiring him to wait until the completion of the code already initiated. As explained hereinbefore, the reset relay a is energized in series with whichever one of the code-setting relays W happens to be energized. If the switching device corresponding to this code-setting relay is operated during the transmission of the corresponding code, contact I!) associated therewith is opened, and the circuit is immediately interrupted for both the code-setting relay and the reset relay a. Thus, if switching device BEI has been operated, and the corresponding code is being delivered, the code-setting relay BW will be energized in series with reset relay a. If, now, switching device BE! is restored to its original position, contact l9 controlled thereby will be operated briefly during transit of the lever l2, thereby deenergizing relays BW and a. This causes the contacts on the code-setting relay to be opened, and further operation of the stepping contactor to its starting position can not cause operation of the transmitting relays to produce interruptions in the line circuits. The opening of relay a, however, supplies current directly to the transmitting relay AT3 over back contact 68 of relay (1 and front contact 61 of relay 1). The energization of relay AT3 holds relays AR! and ARZ deenergized so that relay Q is also deenergized, thereby insuring that relays K and H remain energized until the stepping contactor P has completed its cycle of operation and returned the spider 25 to engagement to the segment 2'! for the proper location of the spider to begin the new code.

Referring now to Fig. 2, the line relays BRI and BR? are normally included in the line circuit extending to the dispatchers oifice and to each of the other remote stations. When a control cod-e is transmitted, as explained above, the first interruption of line wires l and 2 (which, it will be remembered, was caused by the preliminary energization of transmitting relay AT3 while contact 2i-2l of stepping contactor P was closed, prior to the beginning of the actual control code) de-energizes both relays BR! and BRZ. These relays control relay Q in a manner similar to the control of relay Q by relays ARI and AR2 at the dispatchers office, and relay Q controls two slow-release relays K and H which function in the same manner as the office relays K and H already described. The. preliminary impulse just described therefore de-energizes relay Q When this happens, current flows from terminal B over back contact I00 of relay Q through relays K and H in parallel to terminal C, thereby energizing the two latter relays. At the conclusion of the preliminary impulse, relays BR! and BB2 again become energized, and relay Q again picks up. This preliminary operation of the relays at the remote station is utilized in checking and locking functions which will be referred to more specifically hereinafter and is not considered as a part of the code. In the control code which was previously described, the first station selecting code element was produced by interrupting line wire 2 and it will be seen that this code element results in the de-energization of relay BB2 without interfering with relay BRI. In this connection, it should be pointed out that the corresponding line relays at each of the other remote stations operate in unison with the line relays at station E, and it is necessary to provide, at each station, apparatus which is selectively responsive to the character of the several code elements and to the sequence in which such code elements are received. Any suitable selecting apparatus may be utilized for this purpose, but for purpose of illustration, I have shown decoding relays, two of which are provided at station B and designated by the reference characters BN1 and BN2. Each of these decoding relays has a holding circuit and three stepping circuits which control a biased movable member progressively away from an initial condition to close a contact 1'! at the end of a predetermined number of steps, in this case six, but only if the stepping circuits are energized in a predetermined sequence corresponding to the code pattern to which the decoding relay is adapted to respond and if the holding circuit is closed during the intervals between successive closings of the stepping circuits. The decoding relays furthermore function in such manner as to allow the movable member to return to its initial condition upon the reception of a selecting element which does not correspond to the particular pattern to which the relay is adapted to respond, so that only the decoding relay which has been operated through five steps in response to the first five elements of the. code will be conditioned to close its contact Ti, the contact 17 of the selected relay becoming closed upon reception of the final element irrespective of the character of that element. One form of decoding relay which will operate in the manner described is disclosed and claimed in co-pending application for Letters Patent of the United States, Serial No. 378,894, filed the 17th day of July, 1929, by Clarence S. Snavely for Remote controlling apparatus. As here shown, the two decoding relays BNI and BN2 are connected in parallel, the holding circuits for these relays including front contacts on both line relays BR! and BRZ. These holding circuits may be traced from terminal B, front contacts 69 and H of relay BR!, front contact 72 of relay BB2, wire 13, thence through the decoding relays BN! and BN2 in parallel to wire 14 and over a front contact !5 of relay H and back con tact 1.6 of relay M to terminal C. Wire 14 extending from the decoding relays over contacts !5 and it of relays H and M to terminal C, also serves as a common return for the Stepping circuits which are controlled over wires e, f, and h. Wire e is connected with terminal B over back contact 7! of relay BRA, front contact 10 of relay BR2 and back contact 69 of relay BR! when relay BR! is de-energized and relay BB2 is energized. When relay BRZ is deenergized and relay BR! is energized, terminal B is connected with wire 1 over front contact 69 of relay BRl, front contact 1! of relay BR! and back contact E2 of relay BRZ. When relays BR! and BB2 are both de-energized, wire it is connected with terminal B over back contact 69 of relay BR! and back contact Iii of relay BB2. Front contact 15 of relay I-I included in the common return for the stepping and holding circuits for the decoding relays closes when relay I-I becomes energized at the beginning of the code, and opens to allow the operated decoding relay to return to normal when relay I-I releases at the end of the code. Back contact 16 of relay M in the common return is opened to prevent the operation of the decoding relays when an indication code is being transmitted fromthe station, as hereinafter described.

The two decoding relays at station B are designed to close their contacts 1'! selectively in response to control codes originating at panel B in the dispatchers oii'lce. It will be remembered that the first four elements selecting of all control codes originating at panel B are the same, and each of these codes will operate both relays BN! and BN2 through four steps. If the switch lever of panel B is reversed, the fifth impulse is produced by opening line wire 2, and when this impulse is received, the decoding relay BN2 at station B advances one step and relay BNI releases. If on the other hand, the switch lever of panel B is normal, the fifth element of the code is produced by opening line wire and in that case, the decoding relay BN! advances one step and relay BN2 releases. When the last element of the control code previously described is received at station B, therefore, relay BN2 selectively closes its contact IT, and since relays BR! and BRZ both become de-energized, terminal B is connected with wire h, and cunrent flows from this wire through the left-hand winding of relay BY3, contact ll of decoding relay BN2, and right-hand winding of relay BY! to terminal C. Relay BY3 holds its contact 85 open and relay BY! reverses to close contact l8'!8 When this happens; apick-up circuit is completed for relay 21 over contact 3? operated by switch 1. Relay p then becomes energized, and an operating circuit is completed for motor 9, from terminal B, over front cont-act 5 '19 of track relay o, front contact 86 of relay p armature ID of motor 9*, front contact 8! of relay p and field of motor 0 to terminal C. When this circuit is closed, motor a operates to drive the switch towards its reverse position. When the switch attains its full reverse position, contact 3'! opens, thereby de-energizing the relays 11 Of course relay BYE is energized for only a brief interval of time during the last element of the control code, but the contacts of this relay remain in the position to which they were last moved.

If the dispatcher wishes to restore switch to its normal position, he returns the switch lever of panel B to the normal position in which it is illustrated in the drawings. This operation results in the transmission, in a manner which will be readily understood from the preceding description, of a control code, similar in all respects to the code previously described, except that since contact !4--!6 of switching device BE! is now closed, the fifth element of the code now transmitted will be produced. by opening line wire instead of line wire 2. When this code is received at station B, the decoding relay BN! selectively closes its contact l! while relay BN2 releases. When the final impulse of the code is received, relays BR! and BRZ are both de-ener gized as before, and current flows. through the left-hand winding of relay BY3 as previously explained, and thence through contact ll of relay BN! and the left-hand winding of relay BYE l to terminal C. Contact lat-13 is therefore closed and an operating circuit is completed for switch relay p over contact 36 controlled by switch 1. Relay p therefore picks up, and completes an operating circuit for motor 9, from terminal B, over front contact 82 of track relay 1), front contact 83 of switch relay p armature Hl of motor a, front contact 84 of relay p and field I! of motor g, to terminal C. When this circuit is closed, the motor 9 operates to drive switch 7 towards its normal position, and when the switch has attained its full normal position, the opening of contact 36 de-energizes relay p to stop the motor 9.

It will be remembered that the character of the last element of each code is determined by the position of the signal lever of the switching device BE2 or of the corresponding switching device of any other panel at which the code originates. When the signal lever occupies its normal position as shown this final element of the code is produced by opening both the line circuits so that relays BR! and BB2 both become de-enei gized, the left-hand winding of relay BYE is energized as described hereinbefore so that contact 85-85 of relay BY3 is open and all signals at station B indicate stop. If a dispatcher wishes to clear an eastbound signal at station B, he may do so by moving the signal lever of the switching device BE2 to its left-hand position in which contact i l-i5 is closed, so that the final element of the code then transmitted is produced by opening line wire When this code is received at station B, relay BR! is de-energized during the final code element, and current flows from terminal B to wire e and thence through the left-hand winding of relay BYZ and the righthand winding of relay BYE and thence through the contact of one or the other of relays BM! or BN2, depending upon the position of the switching device BE! on panel B at the dispa-tchers office, and the corresponding winding of relay BYi to terminal C. When this happens, contact 8586 of relay BY? is closed, if this contact is not already closed, and contact 85 of relay BY3 is also closed. A circuit is then completed for signal relay q current flowing from terminal B, over contact 85-65 of relay BY3, contact B'686 of relay BY2, and winding of relay q to terminal C. Assuming that the switch 2 occupies its normal position, so that the relay is is energized to swing its polar contacts to the left, the energization of relay q completes a circuit for signal w from terminal B, over front contact 87 of track relay 2), front contact 88 of relay q front contact 89 of relay it, normal contact 99 of relay k, and the operating mechanism of signal 1.0 to terminal C. Of course, if the switch lever is reversed and the signal lever is moved to the left the fifth element of the code is produced by interrupting line wire 2 so that the switch I at station 13 is moved to its reverse position, and the final element of the code is produced by interrupting line wire i sothat signal relay q becomes energized as described above, but in this case the operating circuit for signal is completed from terminal B over front contact 31 of track relay 1), front contact 38 of relay q front contact 83 of relay is, reverse contact 96 of relay k and operating mechanism of signal w to terminal C.

If, however, the switch lever of the switching device BEi occupies the normal position in which it is illustrated on Fig. 1, and the signal lever of the switching device BBB is operated to the right to close contact 54-57, the control code then delivered to station B has its fifth element formed by interrupting line wire I and has its sixth element formed by opening line wire 2, and at station B a circuit is closed during the sixth element of this code from terminal B to wire 7 and thence through the right-hand winding of relay B322 and the right-hand winding of relay BY3, contact Ti of relay BNi, and the left hand winding of relay BYi to terminal C.

Current then flows from terminal B over contact $35-$5 of relay BYS, contact 8886 of relay BYE, and winding of relay q to terminal C. Relay q therefore becomes energized and current flOWS from terminal B over front contact 8? of track relay 1), front contact 9! of relay q front contact 92 of relay 70, normal contact 93 of relay k, and operating mechanism of signal 10 to terminal 0. If, however, the switch 1 occupies its reverse position when signal relay q is energized, relay it would occupy a position in which its polar contacts were swung to the right and an operating circuit would then be closed for signal 10 from terminal B, over front contact 81 of track relay '0, front contact 9| of relay q front contact 92 of relay 7c, reverse contact 93 of relay is, and operating mechanism of signal w to terminal C.

All signals can be restored to the stop position by restoring the signal lever of the switching deto the left-hand winding of relay BY3 thereby opening contact 85-85 of this relay and deenergizing both signal relays q and as explained above in connection with the operation of the switch.

It should be pointed out that with the apparatus thus far described, I have provided apparatus which controls both the switch and signals at a remote station, in accordance with the position of the control levers on the corresponding panel at the dispatchers oifice with a single code. That is to say, only one control code is required to position all apparatus at one station, in accordance with the positions then occupied by the control levers on the corresponding panel in the dispatchers ofiice.

In order to inform the dispatcher concerning the condition of apparatus at the several remote stations, each remote station is provided with apparatus for delivering to the line circuits, indication codes for operating the line relays at the dispatchers ofiice in accordance with the condition of the apparatus at the remote station. Referring particularly to the apparatus located at station B, Fig. 2 illustrates indication code transmitting apparatus which includes a plurality of delivery units, here shown as three in number and designated by the reference characters G G: and G Each of these delivery units is similar to the coding units disclosed and claimed in an application for Letters Patent of the United States, Serial No. 254,684, filed by Clarence S. Snavely on Feb. 16, 1928, for Railway traffic controlling apparatus. Each of the delivery units G comprises a storing magnet r having an armature which is biased to the right by a spring v When the storing magnet is ener- I contact 8'5. gized, the armature is moved to its left hand or attracted position, thereby closing front contact 91', and a latch Ml then drops into a position in which the armature is mechanically held in its attracted position. Each delivery unit also comprises a delivery magnet (1 provided with an armature which operates a trigger 142. If a storing magnet r is energized and the associated delivery magnet d is then energized, the trigger M2 is moved to the left, thereby lifting the latch Hll of the storing magnet and releasing the armature of the storing magnet. It should be observed, however, that when the trigger ]42 is held in its left-hand position by energization of the magnet d, the armature of the storing magnet r is held in its left or attracted position, even though the storing magnet may be electrically de-energized.

In addition to the delivery units G, the indication code transmission equipment at each remote station comprises a stepping contactor and stepping magnet designated by the reference characters P and F with distinguishing exponents, and a group of relays associated therewith and similar in function to the relays L K M V H D and J at the dispatchers office. 1

In explaining the operation of the equipment during the transmission of an indication code, I will first assume that switch 1 at station B is being moved to its reverse position. Relay p is energized during this movement of the switch, and when the switch attains its full reverse position, contact 94-94" becomes closed and cur rent flows from terminal B over contact 94-434 front contact H? of relay 11 through the righthand winding of relay i and winding of storing magnet r of delivery unit G to terminal C. Of course relay p becomes de-energized when the switch attains its reverse position, and the circuit just traced is closed for only a brief interval of time, but during this brief interval the armature of the storing magnet r of unit G is attracted and latched, and contact 969B of relay 2' becomes closed.

Relay L is normally held energized over a circuit which may be traced from terminal 13 through back contact 98 of relay V contact 4 5 M of relay J resistor 99, thence through the back contact 9'5 of the storing magnets r of all of the delivery units G in series, and the winding of relay L to terminal C. When the storing magnet r of unit G is energized, as described above, the circuit just traced for relay L is interrupted, so that the back contact I03 of this relay becomes closed. This operation completes a pick-up circuit for relay BS which may be traced from terminal B, over front contact Mil of relay Q back contact lill of relay K winding of relay BS, and back contact :03 of relay L to terminal 0. Relay BS now becomes energized, and the opening of back contacts H35 and m5 of this relay opens the line wires i and 2 to all stations more remote from the dispatchers office than station B. Furthermore, the closing of front contacts Hi l and "25 connects the line wires i and 2 to the dispatchers ofiice through the line relays BRl and BB2, respectively, and through back contacts on the transmitting relays BTi, BTZ and BTS, with the common return wire 3, Relays BR! and BB2 therefore remain energized if the line is clear between station B and the dispatchers office. When relay BS becomes energized, however, a circuit is completed for relay BT3, from terminal B, over front contact use of relay Q back contact ill! of relay K back contact ill? of magnet F contact 26-47 of stepping contactor P winding of relay BT3, and front contact MS of relay BS, to terminal C. Relay BI3 then becomes energized and interrupts line wires l and 2 to the dispatchers office at back contacts E68 and H39, respectively. This operation de-energizes relays BRl and BR? and also de-energizes all line relays at the dispatchers office and at all remote stations between station B and the dispatchers office. t station B, relay Q is tie-energized, and the closing of back contact lilil of this relay closes the circuits for relays H and K whereupon these relays become energized. When relay K becomes energized, the circuits previously traced for relays BS and BT35 are opened, so that these relays become de-energized. Relay BS, however, is slow-releasing and holds its front contact closed until current is again supplied to this relay, as will be described hereinafter. Relay BTB, however, releases, thereby restoring the line circuits i and 2 to the dispatchers office. Relays BR! and BB2 then become energized, and hence pick up relay Q whereupon a circuit is closed for relay M from terminal B, over front contact I69 of relay Q front contact lEll of relay K winding of relay M front contact Hi l of relay BS, and back contact I03 of relay L to. terminal C. The circuit just traced is provided with a branch which passes from one terminal of relay M through back contact llil of relay V back contact HI of relay D winding of magnet F and thence as before, over front contact I44 of relay BS and back contact I03 of relay L to terminal C. When the circuit and its branch just described are closed, relay M and magnet F become energized. When magnet F picks up, its back contact I01 opens, and its front contact closes, thereby breaking the circuit to the spider 26 of stepping contactor P and energizing relay D over a circuit which may be traced from terminal B, through front contact H2 of relay M front contact if]? of magnet F and winding of relay D to terminal C. Magnet F and relay D thereafter operate to advance stepping contactor P in a manner which will be apparent from the previous description of the operation of the stepping contactor P at the dispatchers ofiice. It will be observed that, as shown in the drawings, the spider 25 of contactor P rotates in a counter-clockwise direction.

When relay M became energized, it completed a stick circuit over its own front contact H3 and also restored energy to relay BS over a circuit which includes front contact H2 of relay M and back contact 33 of relay L Furthermore, the closing of front contact l6 of relay M completes the circuit for the delivery magnet d of unit G This circuit may be traced from terminal B over back contact 98 of relay V contact 44t i of relay J resistor 99, back contact 91 of storing magnet r of unit G front contact 9? of storing magnet r of unit (3?, winding of delivery magnet cl of unit G and front contact 16 of relay M to terminal C. The delivery magnet d of unit G then becomes energized and moves trigger M2 into engagement with the armature of storing magnet r, This operation releases the latch Ml but holds front contact 91 of the storing magnet closed until the delivery magnet cZ subsequently becomes de-energized. When'the delivery magnet (1 closes its front contacts, the right-hand winding of master relay J is connected across the resistor 99 over a circuit which may be traced from one terminal of the resistor through contact it-M of relay J the right-hand winding of relay J front contact H4 of delivery magnet d, front contact 91 of the storing magnet r of unit G and back contact 97 of storing magnet r of unit G back to the other terminal of the resistor 99. The potential drop across resistor 99 due to current flowing through this resistor to the delivery magnet 01 is sufiicient to energize the relay J which then swings its contact to the right to close contact i t-M The operation of the stepping contactor P described above, connects spider 26 successively with segments 28, 29, 36 and 3i and energizes selected ones of the transmitting relays BTI, BT23, and BT3 in a predetermined sequence to produce the first four elements of an indication code. These first four elements are utilized to select, at the despatchers office, a particular control panel corresponding to the station at which the indication code originates and for convenience I prefer to utilize, for indication codes from a particular station, the same sequence of code elements that is used in the control codes for operating apparatus at such remote station; however, this particular arrangement is not essential but only desirable because of the resulting economy in the total number of codes necessary to control a given number of stations,- The decoding relays BNI and BN2 however do not respond when indication codes are transmitted from the same station, because relay M is then energized and the common return wire 14 is open at back contact 16.

g The first four elements of all indication codes originating at station B are the same, but when 1.5-.

the spider 26 engages segment 32 to produce the fifth element of the code now being described, a circuit is completed, from terminal B, over front contact H2 of relay M back contact it? of relay F contact 26-32 of stepping contactor P front contact l iii of delivery magnet d of unit G and winding of relay BT2, to terminal 0. The fifth element of the code is therefore produced by opening line wire 2. In similar manner the sixth element of the code is produced by opening line wire 2, the circuit for relay BT2 during the sixth element of the code passing from terminal B, over front contact H2 of relay M back contact Iel of relay F contact Zfi33 of contactor P front contact us of delivery magnet 01 of unit G contact 9396 of relay 2' (which, it will be remembered was closed as a result of the reversal of switch 1), and winding of relay BT2 to terminal C. In similar manner, the fifth and sixth elements of each indication code are determined by the delivery magnets (31 of the units G in conjunction with the relays i and 2 After the completion of an indication code, the stepping contactor P moves the spider 26 into engagement with segment 3 When this happens, relay V is energized over a circuit which is obvious from the drawings, and the circuit is then interrupted for the delivery magnet 01 of unit G which releases its armature and permits trigger M2 to release the armature of storing magnet 1". Furthermore, a circuit is completed over front contact 98 of relay V for the left hand winding of master relay J so that contact i i4i of this relay becomes closed. The energization of relay V also interrupts the circuit for relay F and spider 26 of stepping contactor P pauses in engagement with segment 35. When the contactor is in this position, however, the line circuits are closed so that relays BRA, BRZ and Q are energized. Relays H and K are therefore Lie-energized, and after the expiration of a brief interval of time, relay H releases. When this happens, current is again supplied to relay F from terminal B over front contact ll? of relay M back contact $5 of relay I-I back contact ill of relay D winding of relay F front contact 1M of relay BS and back contact H33 of relay L The energization of relay F interrupts the circuit previously traced for relay V and allows the latter relay to release in case there is no storin magnet T energized. The de-energization of relay V completes the circuit for the starting relay L and when this relay picks up, it breaks the circuit for relays BS and M and these relays both become de-energized. When relay M opens its front contacts, relay F becomes de-energized and since the remaining relays at station B are now tie-energized, it follows that the apparatus is restored to its normal position. It should be noted that the final de-energization of relay F restores the spider 26 of stepping contactor P to engagement with segment 2'! so that the apparatus is left in condition for delivery of a new code.

It should also be pointed out that when relay BS becomes de-energized, the line circuits are reestablished to all stations beyond station B.

For the purpose of indicating the character of the indication codes received at the dispatchers office, the line relays AR! and AR2 control decoding relays Bnl and B112 similar in all respects to the decoding relays BNl and BN2 described in connection with the apparatus located at station B. Each panel at the dispatchers oflice will be provided with decoding relays n which will be arranged to close their contacts Ti only in response to indication codes originating at the station corresponding to such panel. For example, relay Bni on panel B closes its contact 11 only when an indication code originating at station B has its fifth element produced by opening line wire and decoding relay Bn2 is arranged to close its contact ll only if the indication code received from station B has its fifth element produced by opening line wire 2. The wires e, f, and h control the stepping circuits of the decodiug relays n in accordance with the character and sequence of the received indication code elements the same manner as described in connection with the apparatus at station B. Thus, when a coding element is produced by opening line wire l terminal B is connected with Wire 6, when a code element is produced by opening line wire 2, terminal B is connected with line wire and when the code element is produced by opening both line elements 5 and 2, terminal B is connected with wire it.

When the indication code previously described is received from station B as a result of the movement of the switch I to its reverse position, relay Bn2 becomes selectively energized. When the sixth element of the code is received, terminal B is connected with wire 3, and current flows from this wire through the right hand winding of relay By! and contact T! of decoding relay B112 to terminal C. Contact i2fll2fl of relay By! therefore becomes energized and current is supplied over this contact to a lamp [2 i, thereby informing the dispatcher that switch I at station B occupies its reverse position.

If the switch is restored to its normal position at station B, a circuit is completed for a brief interval over contact 9 i9t= operated by the switch, and front contact of switch relay p through the left hand winding of relay 2' and the storing magnet r of unit G This operation initiates the delivery of an indication code from station E, the apparatus functioning as described hereinbefore, with the exception that the final element of the indication code now delivered to the line circuit is produced by energizing transmitting relay BT! to open line wire 5. In all other respects, the operation is identical to the transmission of the code previously described so that the reception of this indication code at the dispatchers ofi1ce picks up the decoding relay B112 during the fifth element of the code and when the sixth element of the code is received, terminal B is connected with wire 6 and current flows from this wire through the left hand winding of relay By! and contact ll of relay B112 to terminal C. Contact l2i'3l20 of relay Byl is therefore closed, and current is supplied to lamp 522 to indicate to the dispatcher that the switch l at station B occupies its normal position.

The apparatus is also arranged to inform the dispatcher concerning the condition of the signals at station B. The signal indication is controlled by delivery unit G which is in turn controlled by circuit controllers on the signals and by the signal relays (1 and (1 For example, I will assume that signal 10 is moved to the proceed position. Contact 52:) controlled by signal 10 is arranged to close for a brief interval just before the signal attains its proceed position. At this time relay q is energized, and a circuit is then completed from terminal B, over front contact 227 of relay q and contact !.29 controlled by signal w through the right hand winding of relay i and storing magnet r of unit G to terminal C. The circuit just traced is provided with a branch around contact 129 including a similar contact l3i operated by signal 111 just before this signal reaches its proceed position. Another branch for the circuit just traced, may be traced from terminal B over front contact i3? of relay (12 and contact E33 operated by signal w Still another branch for this circuit may be traced from terminal B over front contact 32 of relay q'- and contact :34 operated by signal and thence as before to the right hand winding of relay i It follows therefore, that when any signal moves to the proceed position, a circuit is closed which energizes the storing magnet r of unit G and closes contact Est-5351 of relay 2' The apparatus at station B then operates to deliver an indication code to the dispatch-ers ofiice and the parts are so arranged that the fifth element of this indication code is produced by opening line wire i, thereby selectively energizing the decoding relay Bni at the ofiice. The sixth element of this indication code is produced by energizing relay BTS so that both line wires to the dispatchers ofiice are opened and as a result, terminal B is connected with wire it at the dispatchers oifice during the final element of the indication code. During this final element of the code, current flows from wire it through the right hand winding of relay B142 and contact ll of relay Bill to terminal C. Contact Il9i E9 of relay ByE is therefore closed, and current is supplied over this contact to lamp l39to indicate to the dispatcher that a signal at station B occupies the proceed position.

The indication of the return of a signal to its stop position is similar to the indication of the proceed position, and is accomplished by contacts I35, I35, i3? and H8 controlled by signals 2o m 10- and w respectively, in such manner that each contact is closed for a brief interval during movement of the corresponding signal from its proceed to its stop position just prior to the instant that the signal attains its full stop position. When any signal returns to its stop position, a circuit is completed for the left hand winding of relay 1' and the storing magnet r of unit G It is unnecessary to trace all of these circuits in detail and for purposes of illustration, I will assume that signal returns to its stop position. Current then flows from terminal B, over back contact i2? of relay q contact I operated by signal w left hand winding of relay 2' and winding of storing magnet r of delivery unit G to terminal C. The energization of storing magnet r initiates the transmission of an indication code from station B, and since this indication. code has its fifth element produced by opening line wire 5, the decoding relay Bnl on panel B at the dispatchers office becomes selectively energized. During the sixth element of the code, however, relay ET? is energized over contact iilsl3il of relay i so that line wire 2 is opened to produce the last element of the code and as a result, at the dispatchers office, terminal B is connected with wire f and current flows from this wire through the left hand winding of relay BW and contact ll of relay Bni to terminal C. Contact lie-9 of relay IBM is then closed to light lamp M0 and thereby indicate to the dispatcher that a signal at station B has moved to the stop position.

In addition to information concerning the position of the devices at a station which are controlled by the dispatcher from his ofiice, it is sometimes desirable to give him information concerning traffic conditions adjacent this device. For example, it might be desirable for the dispatcher to know when a train leaves the track section i at station E. For this purpose, I provide a repeater relay 2 controlled by front contact I 25 of track relay v. Relay 2 is therefore normally energized when the section 5% is unoccupied but is de-energized when the section is occupied. The relay 2 is somewhat slow-acting so that when a train leaves section 5$, thereby allowing relay 1) to become energized, a brief interval of time elapses before relay 2 opens its back contacts. During this brief interval of time a circuit is completed for the storing magnet r of delivery unit G This circuit may be traced from terminal B, over front contact I23 of relay 1) and back contact i2 1 of relay .2, through winding of storing magnet r to terminal C. When the storing magnet 1' becomes energized, the apparatus operates to deliver an indication code to the line circuits, and it will be seen from the drawings that the fifth element of this indication code is. produced by energizing relay BTI so that line wire i is opened and decoding relay Bnl at the dispatchers ofiice becomes selectively energized. The sixth element of the indication code is also produced by energizing relay BTl so that during this sixth-element of the code, the wire e at the dispatchers ofiice is connected with terminal B, and current flows from this wire through magnet i726 of a graphic train recorder and contact ll of relay Bni to terminal C. The magnet 526 is shown only by way of example and might be replaced by any other suitable indicating device. The operation of this magnet therefore indicates to the dispatcher the fact that a train has left section 55 at station E.

It is, of course, understood that the lamps I2], 222, i355 and Hit at the dispatchers ofiice are associated with panel B and would ordinarily be located on the control panel adjacent the levers which operate the switching devices BE! and BE2 which have been illustrated apart from this panel for purposes of simplicity.

Attention should also be drawn particularly to the fact that the apparatus at the dispatchers office and at each remote station including the sectionalizing relays AS, BS, etc.,. and the relays K, M, H, etc., operate to provide checking and locking functions which prevent the transmission of code to the line circuits from any station when another station is transmitting a code. These checking and locking operations are described in detail in the Snavely application, Serial No. 362,948 identified above.

It will be plain from the foregoing that I have herein shown and described a code system of communication, control, and indication, in which a plurality of direct wire line circuits are separately controlled to give distinctive code elements. By combining these code elements in different sequences, I build up different codes for transmitting different control and indication functions. The selection between these different codes may be accomplished in any suitable manner and I do not wish to be limited in any respect to the use of the particular decoding relays which I have illustrated only for purposes of explanation. The only requirement is that some apparatus be utilized which will respond selectively to the sequence in which code elements of different characters are received.

Although I have herein shown and described only one form of remote controlling apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

l. A centralized traflic controlling system for railroads comprising a control ofiice and a station located at spaced points, line wires extending between said two points and affording a plurality of channels of communication between such points, means at each point for creating a series of distinctive code elements by modifying the electrical conditions of said channels individually or in combination, and means at each point selectively responsive to a series of such code elements originating at the other point.

2. A centralized traflic controlling system for railroads comprising a control ofiice and a station located at spaced points, line wires extending between said two points and afiording a plurality of channels of communication between such points, means at each point for creating a series of distinctive code elements by modifying the electrical conditions of said channels separately or in combination, a plurality of circuits at each point each arranged to be closed when an individual one of said code elements is delivered to said channel at the other point, and means at each point selectively controlled in accordance with the sequence in whichthe associated circuits are closed.

3. A centralized trafiic controlling system for railroads comprising a control ofiice and a station located at spaced points, a plurality of line circuits extending between said two points, a plurality of relays at each point each arranged when operated to deliver a code element to a different one or combination of said line circuits, means for operating selected ones of said relays in a predetermined sequence, and means at each point selectively responsive to the sequence in which code elements are delivered to said line circuit or combinations of line circuits at the other point.

4. In combination, two line circuits extending between two spaced points, and each including a line relay at one said point, a first and a second transmitting relay at the other point each arranged when operated to control an individual one of said line circuits, a third transmitting relay arranged when operated to control both said line circuits, means for operating selected ones of said transmitting relays in a selected sequence, and means selectively responsive to the sequence of operation of said line relays.

5. In combination, two line circuits extending between two spaced points, and each including a line relay at one said point, a first and a second transmitting relay at the other point each arranged when operated to control an individual one of said line circuits, a third transmitting relay arranged when operated to control both said line circuits, means for operating selected ones of said transmitting relays in a selected sequence, a first circuit arranged to be closed when one said line relay is operated, a second circuit arranged to be closed when the other line relay is operated, a third circuit arranged to be closed when both line relays are operated, and means at said other point selectively controlled by said three circuits and arranged to respond only when selected ones of said circuits are closed in a predetermined sequence.

6. In combination, a plurality of line circuits,

a plurality of transmitting relays each arranged when operated to deliver a code element to a different one or combination of said line circuits, means for operating selected ones of said transmitting relays in a predetermined sequence to produce a complete code, a plurality of receiving devices, one for each line circuit and each arranged to be operated in response to control of the corresponding line circuit by a transmitting relay, and means selectively responsive to the sequence of operation of said receiving devices.

7. In combination a plurality of normally ciosed line circuits each including a source of energy and an individual line relay, a plurality of transmitting relays each arranged when operated to open a different one or combination of said line circuits, means for operating selected ones of said transmittmg relays in a predetermined sequence, and means selectively responsive to the sequence of operation of said line relays.

8. In combination with a plurality of normally closed line circuits each including an individual line relay, manually controlled means for briefly interrupting said line circuits singly or in combination in a predetermined sequence to produce a code, a traific governing device, and means selectively responsive to the sequence of operation of said line relays and actuated by said code to control said device.

9. In combination with a plurality of stations, a plurality of devices at each said stations, a plurality of normally closed line circuits connecting all said stations, means for producing control codes made up of code elements each formed by briefly opening a difierent one or combination of said line circuits, means at each station responsive to the sequence of a portion of the code elements of each code to select a station and means controlled by the remaining elements of each code to operate a selected device at said selected station.

10. In combination with a plurality of normally closed line circuits, a plurality of movable devices, a stepping contactor having a series of contacts and arranged to close the contacts of said series in order when the contactor is actuated, means set into operation by a change in the condition of any said device to actuate said stepping contactor, means operating when any contact of said series is closed to interrupt said line circuits singly or in combination according to the condition of the device which has been operated, means controlled by the last contact of said series for stopping said stepping contactor, and means selectively responsive to the sequence in which said line circuits are opened.

11. A remote control system of the code type comprising a plurality of line circuits extending between two points, a plurality of movable devices at one point, means responsive to a movement of any device for selectively interrupting said circuits singly or in combination to produce code elements in a sequence of which part is determined by the particular device operated and another part by the position into which such device is moved, and means at the other point selectively responsive to the entire sequence of such code elements.

12. A remote control system of the code type comprising a plurality of groups of movable devices, a plurality of line circuits, means responsive to the operation of any device for selectively controlling said circuits singly or in combination to produce code elements in a sequence of which one part is determined in accordance with the group containing the operated device and another part is determined by the position to which .ch device was moved, a plurality of groups of registermechanisms, means controlled by said line circuits for selecting a particular group of said mechanisms in response to said one part of a sequence of code elements, and means for actuating a par-'cular mechanism in the selected group in accordan e with said other part of such sequence.

13. In a centralized traffic controlling system for railroads, a control office and a station located at spaced points, a plurality of line circuits connecting said office and station, a plurality of movable levers at the ofiice, means responsive to an operation of any lever for selectively controlling said circuits singly or in combination to produce a series of code elements of which one part is determined in accordance with the lever which was moved and another part is determined by the position to which such lever was moved, selecting means at the station responsive selectively to said one part of a sequence of codeelements, and registering means at the station controlled by said selecting means and selectively responsive to said other part of said sequence.

i l. In a centralized traffic controlling system for railroads, a control ofilce and a plurality of stations, a plurality of line circuits extending from said oiiice to said stations, a plurality of movable levers at the oflice, means responsive to an operation of any lever for selectively controlling said circuits singly or in combination to pro-- duce a series of code elements of which one partis determined in accordance with the lever which was moved and another part is determined by the position to which such lever was moved, selecting means at each station responsive selectively to said one part of a particular sequence of code elements, and registering means at each station. controlled by the associated selecting means and selectively responsive to said other part of a sequence.

15. In a centralized traliic controlling system. for railroads, a control office and a station connected by a plurality of line circuits, means at the station for at times controlling said line cir cuits singly or in cor bination to produce a series of code elements. in a sequence or which one part is determined by the particular station and. another part is determined by trafiic conditions at such station, selecting means at said oifice responsive selectively to said one part of a se-- quence, indication means. at the office controlled by said selecting means and selectively responsive to said other part of saidsequence.

16. In a centralized traffic controlling system: for railroads, a. control office and a plurality of' stations, a plurality of line circuits extending from said ofiice to said stations, means at each. station for at times controlling said line circuits singly or in combination to produce a series of' code elements in a sequence of which a part is determined by the station at which such sequenceoriginates and another part is determined by traffic conditions at such station, a plurality of panels at the oflice each provided with indication mechanism, means for selecting a particularpanel in accordance with said one part of a sequence of code elements, and means for controlling the indication mechanism for the selected. panel in accordance with said other part of such sequence.

1'1. In combination with line wires providing a plurality of communication channels, a plurality of movable devices, a code setting relay for each said device each arranged to be operated in response to movement of the corresponding device, and transmitting means for controlling said channels singly or in combination to produce a series of code elements in a sequence of which one part is determined by the code setting relay which is operated and another part is determined by the position of the corresponding device.

18. In combination with line wires providing a plurality of communication channels, a plurality of movable devices, a code setting relay for each said device each arranged to be operated in response to movement of the corresponding device, and transmitting means set into operation upon the movement of a device for controlling said channels singly or in combination to produce a series or" code elements in a sequence of which one part is determined by the code setting relay which is operated and another part is determined by the position of the corresponding device.

19. In a remote control system of the code type comprising line wires forming a plurality of communication channels selectively controlled singly or in combination in different sequences to produce code elements in diiier-ent patterns, receiving means comprising a selector normally in one condition, and means controlled by said code elements for advancing said selector progressively away from said one condition in re sponse to a particular code pattern, but for allowing said selector to r turn to said one condition upon the'reception of a code element not corresponding to said particular pattern.

20. Apparatus for communicating between two spaced points comprising means for establishing 'a plurality of communication channels between :such points, means at one point for repeatedly controllin said channels to create a series of distinctive code elements during each of which one or another of said channels is controlled singly or a plurality of said channels is controlled in combination, a plurality of receiving relays at the other point operating selectively in response to the character of each said code element, and means controlled progressively by successive operations of said receiving relays and selectively responsive to the condition of such relays during each code element.

21. Apparatus for communicating between two points and comprising a plurality of line circuits extending between such points, means at one point for briefly interrupting said line circuits singly or in combination to produce a series of code elements in selected sequence, a plurality of normally energized line relays one included in each said line circuit and all located at the other said point, means for energizing all of said line relays during each interval between successive code elements, and means controlled progressive- .ly by said code elements and selectively responsive to the particular one or combination of said line relays deenergized during each code element.

22. In combination a plurality of line circuits, a plurality of transmitting relays having back contacts each included in a diiierent one or combination of said line circuits, and means for briefly energizing said transmitting relays selectively to periodically open said line circuits in a predetermined sequence.

23. In combination with a plurality of line circuits, a plurality of transmitting relays having or combination of said line circuits, a series of contacts, means for operating the contacts of said series in succession, and means effective when any contact of said series is closed to briefly energize a selected one of said transmitting relays to open the corresponding line circuits.

24. In a remote control system of the code type, a plurality of line circuits, a plurality of transmitting relays each arranged when energized to open a difierent one or combination of said line circuits, a movable device, stepping mechanism, means responsive to a movement of said device to actuate said stepping mechanism, and means controlled by said stepping mechanism for briefly energizing selected ones of said transmitting relays in a predetermined sequence which depends upon the position of said device.

25. In a remote control system of the code type, a plurality of line circuits, a plurality of transitting relays each arranged when energized to open a different one or combination of said line circuits, a movable device, stepping mechanism, means responsive to a movement of said device to initiate operation of said stepping mechanism, other means for subsequently continuing the operation of said stepping mechanism through a complete cycle, and means controlled by said stepping mechanism for briefly energizing selected ones of said transmitting relays in a predetermined sequence which depends upon the position of said device.

26. In a remote control system of the code type, a plurality of line circuits, a plurality of trans mitting relays each arranged when energized to open a diiferent one or combination of said line circuits, a plurality of movable devices, stepping mechanism, means responsive to a movement of any device to actuate said stepping mechanism, and means controlled by said stepping mechanism for briefly energizing selected ones of said transmitting relays in a predetermined sequence one part of which is determined by the device which was moved and another part of which is determined by the position occupied by the device after such movement.

27. Transmitting apparatus for a remote controlling system of the code type comprising a plurality of normally closed line circuits, a plurality of transmitting relays each effective when energized to open a different one or combination or" said line circuits, and means for selectively energizing said transmitting relays for brief in tervals in a definite sequence.

28. In combination with a plurality of normally closed line circuits, a plurality of stations each comprising a transmitter for selectively interrupting said line circuits in predetermined sequences, a slow releasing relay at each station for preventing initiation of the operation of the corresponding transmitter when the relay armature is in attracted position, a quick releasing relay included in each line circuit at each station, and means effective when any quick releasing relay is deenergized to energize the associated slow releasing relay.

29. In combination with a plurality of normally closed line circuits, a plurality of stations each comprising a transmitter for selectively interrupting said line circuits in predetermined sequences to form a signal, a slow releasing relay at each station for preventing the initiation of the operation of the corresponding transmitter when the relay armature is in attracted position, the time required for said relay to release being greater than the interval between successive interruptions in said signal, a quick releasing relay included in each line circuit at each station, and means effective when any quick releasing relay is deenergized to energize the associated slow releasing relay.

30. In combination with a plurality of circuits controlled selectively in a predetermined sequence, a plurality of line relays one in each said line circuit, receiving means selectively responsive to the sequence of operation of said line relays, means responsive to a first operation of any said line relay for placing said receiving means under the control of said line relays, and means effective upon the cessation of operation of said line relays for removing said receiving means from the control of said line relays.

31. In combination with a plurality of normally closed line circuits selectively interrupted in predetermined sequence, a plurality of line relays one included in each said line circuit, receiving means selectively responsive to the sequence in which said line relays are deenergized, means responsive to the first operation of any said line relay to place the receiving means under the control of said line relays, and means effective when said line relays are all steadily energized to remove the receiving means from control by said line relays.

32. In combination with a plurality of circuits controlled selectively in a predetermined sequence, a plurality of line relays one in each said line circuit, a normally open contact, means for closing said contact upon the first operation of any line relay andfor reopening said contact upon the cessation of operation of the line relays, and receiving means selectively responsive to the sequence of operation of said line relays provided only said contact is closed.

33. In a remote control system comprising a plurality of normally closed line circuits each .licluding a line relay, means for selectively opening said line circuits in a predetermined sequence to produce a code, a slow-releasing relay arranged to be energized when any one of said line relays is deenergized, and receiving means efiective when said slow releasing relay is energized to respond selectively to the sequence in which said line relays are deenergized.

34. In a remote control system comprising a plurality of normally closed line circuits each including a line relay, means for selectively opening said line circuits in a predetermined sequence to produce a code, a slow releasing relay arranged to be energized when any one of said line relays is deenergized, and receiving means controlled by a front contact of said slow releasing relay and selectively responsive to the sequence in which said line relays are deenergized.

35. In combination, a stretch of railway track divided into a plurality of sections, a central office having a plurality of indicators one for each section, a plurality of normally closed line circuits extending along said stretch of track, a transmitter at each section for briefly interrupting said line circuits singly or in combination in a definite sequence to produce a distinctive code, and receiving means responsive to the sequence of interruption of said line circuits to selectively control said indicators.

36. In combination, a stretch of railway track divided into a plurality of sections, a central oflice having a plurality of indicators one for each section, a plurality of normally closed line circuits extending along said stretch of track, a

transmitter at each section for briefly interrupting said line circuits singly or in combination in a definite sequence to produce a distinctive code, and receiving meansresponsive to the sequence of interruption of said line circuits to select the indicator corresponding to a particular station in accordance with the code transmitted over said line wires.

3'7. In combination, a stretch of railway track divided into a plurality of sections, a central ofiice having a plurality of indicators one for each section, a plurality of normally closed line circuits extending along said stretch of track, a transmitter at each section for briefly interrupting line circuits singly or in combination in a definite sequence to produce a distinctive code depending upon traflic conditions in the associated section, and receiving means responsive to the sequence of interruption of said line circuits to select the indicator corresponding to the operating transmitter and to control such selected indicator selectively in accordance with the code transmitted over said line wires.

38. In combination, a stretch of railway track having a series of tramc governing devices distributed along the stretch, a plurality of line circuits extending along said stretch, a transmitter for each device for briefly interrupting said line circuits singly or in combination in a definite with the character of the code received.

39. In combination, a stretch of railway track having a series of traffic governing devices distributed along the stretch, a plurality of line circuits extending along said stretch, a transmitter for each device set into operation by a change in the condition of the corresponding device to briefly interrupt said line circuits singly or in combination in a definite sequence to produce a distinctive code depending upon the condition of the associated device, a central oifice having a plurality of indicators one for each said device, and receiving means responsive to the sequence of interruptions in said line circuit during each code for controlling the indicator corresponding to the device which initiated the code in accordance with the character of such code.

40. In combination, a stretch of railway track having a series of traffic governing devices custributed along the stretch, a plurality of line circuits extending along said stretch, a transmitter for each device set into operation by a change in the condition of the corresponding device to briefly interrupt said line circuits singly or in combination in a definite sequence to produce a distinctive code depending upon the condition of the associated device, a central office having a plurality of indicators one for each said device, receiving means responsive to the sequence of interruptions in said line circuit during each code for controlling the indicator corresponding to the device which initiated the code in accordance with'the character of such code, and means for preventing the simultaneous operation of two of said transmitters.

ll. In combination with a stretch of railway track having a series of traflic governing devices distributed along the stretch, a central oflice having a plurality of movable levers one for each said device, a plurality of line circuits extending from said office along said stretch, a transmitter at said ofice set into operation by the operation of any said lever to briefly interrupt said line circuits singly or in combination in a definite sequence to produce a distinctive code depending upon the particular lever which was operated and the position into which such lever was operated, and receiving means for each said device responsive to the sequence of interruptions in said line cir-'- cuits to control the particular device associated with the operated lever in accordance with the received code.

42. A centralized traiiic controlling system for railroads, comprising a control ofiice and a sta-' tion, line wires connecting said omce and station and affording a plurality of channels of communication between said oilice and station, means at series of code elements by modifying the electrical conditions of said channels individually or in combination, and receiving means at the ofiice and at the station each selectively responsive to said elements and to the sequence in which such elements occur in a code transmitted from the other end of such line wires.

43. A centralized traiiio controlling system for railroads, comprising a control office and a station, line wires connecting said oflice and station and affording a plurality of normally closed and. e

energized channels of communication between said oflice and station, means at the office and at the station for briefly interrupting said channels individually or in combination to produce a series of code elements, and receiving means at the office and at the station each selectively responsive to the particular channel interrupted during a code element and to the sequence of such elements in a code transmitted from the other end of such line wires.

44:. In a remote control system a plurality of normally closed line circuits extending from a despatchers oflice through a plurality of line stations in series, means at the oflice for opening said circuits selectively in a definite sequence to pro-" normally closed line circuits each including a line relay, transmitting means effective when operated to open said line circuits selectively in a definite sequence to produce a complete code of separate code elements, a slow releasing checking relay arranged to be energized when any of said line relays is deenergized, means effective when said checking relay is open to initiate operation of said transmitting means, and means requiring said checking relay to be closed to permit the completion of. the operation of said transmitting means.

46. In a remote control system, a plurality of normally closed line circuits each including a line relay, transmitting means eiTective when operated to open said line circuits selectively in a definite sequence to produce a complete code of separate code elements, a slow releasing checking relay arranged to be energized when any of said the office and at the station for creating a line relays is deenergized, means effective when of said transmitting means, and means requiring said checking relay to be closed to permit the compl tion of the operation of said transmitting means.

47. In a remote control system, a plurality of normally closed line circuits each including a line relay, transmitting means effective when operated to open said iine circuits selectively in a definite sequence to produce a complete code of separate code elements, a first slow releasing checking relay arranged to be energized when any of said line relays is deenergized, a second checking relay arranged to be energized when all said line relays are energized, means controlled by a back contact of said first checking relay and a front contact of said second checking relay for initiating the operation of said transmitting means, and means controlled by front contacts of both said checking relays for completing the operation of said transmitting means.

48. In a remote control system, a plurality of normally closed line circuits each including a line relay, transmitting means effective when operated to open said line circuits selectively in a definite sequence to produce a complete code of separate code elements, a first slow releasing checking relay arranged to be energized when any of said line relays is deenergized, a second checking relay arranged to be energized when all said line relays are energized, means controlled by a back contact of said first checking relay and a front contact of said second checking relay for initiating operation of said transmitting means, and means selectively responsive to. the character of the first element of the resulting code for completing the operation of said transmitting means.

49. In a remote control system, a plurality of normally closed line circuits each including a line relay, means for selectively opening said line circuits in a definite sequence to produce a complete code of separate code elements, receiving means selectively responsive to said code, a slow releasing checking relay arranged to be energized when any of said line relays is deenergized, a device selectively responsive to the first element of a code, and means controlled by said checking relay and by said device for controlling said receiving means.

50. In a remote control system, a plurality of normally closed line circuits each including a line relay, means for selectively opening said line circuits in a definite sequence to produce a complete code of separate code elements, receiving means selectively responsive to said code, a slow releasing checking relay arranged to be energized when any of said line relays is deenergized, a

device selectively responsive to the first element of a code, and means controlled by a front contact of said checking relay and by said device for controlling said receiving means.

51. In a remote control system, a plurality of normally closed line circuits each including a line relay, transmitting means for selectively opening said line circuits in a definite sequence to produce a complete code of separate elements, a repeating relay arranged to be energized only when all of said line relays are energized, a slow release checking relay controlled by said repeating relay, and means controlled by said repeating relay and said slow release relay for controlling said transmitting means.

52. In a remote control system, a plurality of normally closed line circuits each including a line relay, means for selectively opening said line circuits in a definite sequence to produce a complete code of separate elements, receiving means selectively responsive to said code, a repeating relay arranged to be energized only when all of said line relays are energized, a slow release checking relay controlled by said repeating relay, and means controlled by said slow release relay for controlling said receiving means.

53. Remote controlling apparatus comprising a plurality of transmitting relays, a plurality of line circuits each including a contact of an individual one of said transmitter relays and a contact of an additional transmitter relay which controls all said line circuits, and means for operating said transmitter relays selectively in a predetermined sequence to produce a code.

54. In combination with a plurality of line 1 circuits extending between two spaced points, a plurality of transmitter relays at each point each having a contact included in a difierent one of said line circuits, an additional transmitter relay at each point having a contact in each of said line circuits, and means at each point for selectively operating the transmitter relays at such point in a predetermined sequence to transmit a code to the other said point.

55. In a remote control system of the code type, a plurality of code setting relays, code transmitting means for producing diiferent codes, each made up of a series of code elements, means for setting said transmitting means into operation, means responsive to the first element of a code produced by said transmitting means for operating a selected code setting relay, means controlled by said code setting relay for determining certain elements of the code after said first element, and other means for determining the remaining elements of said code.

ALFRED B. MILLER. 

